Package org.datanucleus.store.rdbms.mapping Description

Package containing mappings for datastore (JDBC) types. These mappings will be mapped via the RDBMSMappingManager to
the various java type mappings in org.datanucleus.store.mapped.mapping.

These are datastore (JDBC) types, and probably most of them are atomic types mapping to atomic java types

Mappings map persistent java fields in PersistenceCapable classes to columns in RDBMS tables. Mappings are also
used to map "non-fields" in PersistenceCapable classes to columns in RDBMS tables. A class using datastore identity
does not have java fields representing primary-keys in RDBMS tables, but as said ealier a Mapping is also applied to
"non-fields". Therefore, a Mapping is applied to:

persistent java fields

datastore identity (primary-key columns)

optimistic columns (columns with version numbers)

index columns (columns indexing an ordered list)

owner columns in unidirectional inverse relationships

adapter columns (additional column added as primary key when the existing columns have datatype not allowed,
by database limitation, to be part of the primary key)

In addition to the representation of columns in tables for PersistenceCapable classes, Mappings are also used for representing
fields in queries.